Patent Document 1, shown below, discloses a lens barrel that includes a moving cylinder, which moves relative to a fixed cylinder while being guided by guide pipes provided on the fixed cylinder, and a front group lens that is guided by guide bars arranged on the moving cylinder.
Patent Document 2, shown below, discloses a lens barrel including guide bars that provide guidance in a movement direction and a lens frame that holds a lens and has a sleeve engaging with the guide bars. A cam follower is arranged on the sleeve, and the lens frame is moved in the direction of the optical axis of the lens according to the rotation of a cam cylinder having a cam groove that engages with the cam follower.